Each time the foot of a runner contacts the ground, considerable force is transmitted through the shoe to the runner's foot. This force tends to push the foot forward in the shoe, causing discomfort. The forward force is offset by friction between the shoe and the foot and by the lacing. In addition, lateral forces cause relative lateral motion between the foot and shoe. These lateral forces not only produce fatigue in the runner's foot, but also tend to stretch and wear the shoe, particularly in the metatarsal region. Also, the lateral forces can offset the upper part of the shoe from the sole such that the runner's foot is not properly aligned over the sole.
An additional force during running is the longitudinal shock transmitted directly from the sole to the runner's foot and leg. This shock can result in runner fatigue and discomfort.
Numerous shoe constructions are shown in the prior art for alleviating the discomfort and wear caused by these forces. U.S. Pat. No. 4,413,431 discloses a shoe with a one-piece reinforcement which extends about the lacing opening and has lateral reinforcing portions. Athletic shoes having lateral reinforcing strips have also been shown in U.S. Pat. Nos. 4,245,408, 4,255,876 and 4,447,967. The prior art structures have certain disadvantages such as a tendency to stretch during use, inability to withstand prolonged wear and lack of wearer comfort. U.S. Pat. No. 4,348,821 discloses a sole structure composed of two parts wherein a rigid upper support member is contoured. The upper support member extends from the heel to the middle part of the ball region and is used in combination with a flexible sole contoured to receive the stiff upper support member. Footwear having projections upwardly extending from a sole toward the wearer's foot are shown in U.S. Pat. Nos. 3,589,037 and 4,095,353.
It is an object of the present invention to provide an athletic shoe having a lateral reinforcing strap to prevent lateral foot movement and extend shoe life.
It is a further object of the present invention to provide an athletic shoe with a dished midsole having an upwardly extending peripheral flange for foot stability.
It is a further object of the present invention to provide an athletic shoe having a removable insert with dimples covering the bottom surface thereof for shock absorption.
It is a further object of the present invention to provide an athletic shoe including a combination of features which improve foot stability and comfort.